Official misrepresentation of Australia’s bicycle helmet law

Abstract

The helmet law has failed to achieve its stated goal of reducing the cost of cycling injuries.
Several government agencies have 
obfuscated this disappointing result through misrepresentation.

The information below is an extract from CRAG submission to the Prime Minister in 2009.
Following this submission, the federal government abandoned its policy of supporting compulsory bicycle helmets.

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Federal authorities’ commitment to compulsory wearing of bicycle helmets has never wavered since 1984 and excessive assurances of its value have continued. Although federal authorities knew of the deficiencies of helmets that Corner et al. had found, they pressed the states and territories to pass laws for compulsory wearing. The federal minister threatened to seek reimbursement of funds in the event of non-compliance and he dismissed his South Australian counterpart’s reservations, arguing that permanent brain injury would be prevented.[17],[18]Federal authorities also criticised an exemption which the Northern Territory granted for adults on cycle paths[19],[20], but their main effort to uphold compulsory wearing was directed to Western Australia.

Western Australia [162-63]

Opposition to compulsory wearing of helmets was strongest far from Canberra, Western Australia being the last state to legislate, in 1992. Its Parliament’s Select Committee on Road Safety reviewed the application of the helmets law to adults in 1994. As this threatened the integrity of the national policy, the Federal Office of Road Safety made a submission which argued for upholding the law  FORS’s argument on the effects of compulsory wearing on fatalities and injuries, and the fall in rates of usage of bicycles is examined here.

Fatalities

FORS presented two graphs which purport to show the effect of compulsory wearing on bicycle fatalities. The first, Figure 1 (with data for 1994 and pedestrians added here), is misleading in not taking any account of the effect of the fall in usage.

Figure 1.  Road user fatalities, Australia (indexed to 1986)

Separate listing of fatalities to children and adults, as in Table 1, together with data from surveys showing declines in cycling post-law [162], makes it possible to correct for both the effects of reduced usage and the general improvement in road safety.

Table 1. Fatalities to road users, Australia 1989 – 1993

YearTotal road usersAdult          ChildPedestriansAdult         ChildBicyclistsAdult          Child
19892505           296428             7354               44
19902093           238344             7647               33
19911915           198292             5135               23
19921783           191297             5324               17
19931775           178284             4730               15
Change, 1989-93-29%         -40%-34%         -36%-44%          -66%

Source of data: FORS, 1997. Road Fatalities Australia: 1996 statistical summary.

The fall in fatalities to all cyclists from 1989 to 1993 can be explained as being the product of improved road safety and declines in cycling of 40 per cent by children and perhaps 20 per cent by adults; it is not evidence that the helmet laws reduced the risk of death. FORS also claimed that the reductions in head injuries and fatalities are far greater than the decline in cycling, but this made no allowance for the general improvement in road safety; the claim is irrelevant.

Injuries

FORS stated that helmets have little or no effect on injuries other than to the head, but this discounted the possibility, well known at the time, that wearing one could change behaviour and the risk of accident. Decreases in head injury in some states were cited, but with no allowance for improved road safety or the declines in cycling. According to FORS, reduction in head injury is the best measure of compulsory wearing, but this highlighted its failure to understand the real problem, namely, how to protect from brain damage and consequent death or chronic disability, not from minor trauma.

For Victoria, FORS noted that in the first year after helmets became compulsory, cyclists’ claims on the Transport Accident Commission (TAC) for head injuries decreased by 51 per cent compared to a fall of 24 per cent in non-head injuries. In the second year, the respective decreases were 70 per cent and 28 per cent. FORS said that Lane and McDermott (1993) ascribed the difference to increased helmet wearing. As the difference would seem to be unaffected by the general improvement in road safety or declines in cycling, it might appear to be persuasive evidence of the efficacy of helmets – until inquiries to the TAC revealed a similar trend for pedestrians. This is shown in Figure 2, the vertical line showing the start of the helmets law. Again, it would appear that the cause of the decline in the risk of head injury was changes in other conditions, not helmets.

Figure 2.  Per cent head injury, of accepted TAC no-fault claims, Victoria

Source of data: Transport Accident Commission, pers. comm. 1.12.95.

 

Usage

FORS discussed the fall in bicycle usage as shown by survey data from Victoria, NSW and Western Australia. For all three states, the declines in cycling that followed the helmet laws were underestimated and similar declines pre-law to post-law which had been measured in Queensland, the ACT and the Northern Territory were disregarded. FORS argued that reductions shown in surveys are not a proven result of helmet laws, which could only be found from much bigger surveys or over a longer time. “Unfortunately, long term data is not available”, it said, but it is government, not fortune, that was to blame for that. It was known in 1985 that cycling had declined when private schools compelled students to wear helmets[21], but FORS’s advice to its Minister on the compulsory helmets proposal did not mention this or the need for monitoring.[22]

Monograph 19

FORS’s Monograph 19 (1997) makes three arguments. The first is that compulsory helmets resulted in serious casualties to cyclists declining by more (33 cent) than all road users (23 per cent), from the 4 years “prior to compulsory wearing” (1987-1990) to the 4 years after (1993-1996), but if 1989, the last year before any helmet laws, is compared with 1993, the first year when all were in force, the respective declines are 31 per cent and 25 per cent, much less different. FORS says use of a 4 year period allows evening out of random variations from year to year, but the argument is specious because the numbers in each year exceed 1000. (By contrast, FORS’s submission to the review of the law in Western Australia, discussed above, claimed a reduction in fatalities by using numbers of less than 200.) Also, it is wrong to include 1990 in the base period because the helmets law came into effect in Victoria mid-year. As casualties to all road users in 1990 were 13 per cent below 1989, those to cyclists being unchanged, this results in further over-statement of the difference in the declines in the two groups from pre- to post-law. Also, FORS disregards the decline in numbers of cyclists. Taking this into account, it is clear that cyclists became worse off compared to other road users [164].

Second, FORS states that helmet wearing rates, as measured from casualty crashes, are negatively correlated with deaths and casualties to cyclists, but it provides no details of statistics or sources. The meaning of the claim is not clear and it is at odds with data on wearing rates of casualties [166].

Third, FORS finds from pooled data for 1988, 1990, 1992 and 1994 from its Fatality File that known wearers of helmets suffered fewer severe head injuries on average than non-wearers. It concludes that the absence of a helmet significantly increased the number of severe injuries by up to 21 cent. It is not clear that the finding has any clinical importance, it not being shown that the number of head injuries was related to fatality, nor even stated that head injury was the cause of death, and the data are confused by a change in coding practice by which multiple injury to a single region of the body was coded as multiple in 1990 but under that region in 1992.[23]Also, the data span a great increase in the wearing of helmets after compulsion, and a change in the standard. In 1988, hard shells were required, but from 1990 cyclists were able to wear soft helmets. A more apt description of FORS’s pooling of data is jumbling together and obscuring the important trends that are shown in Table 3 [165].

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